Hi Drtgirl,
I have a leg length discrepancy (LLD), as does Triskelion girl. There's a thread going where we talk about various approaches to LLDs on the bike:
http://forums.teamestrogen.com/showthread.php?t=21780
I've had success in the past with cleat shimming, but that was with a Look cleat. I haven't tried with an SPD cleat.
Triskelion girl has had a custom crankset made by Tom Slocum of High Sierra Cycles. He also has a drop pedal solution that I'm considering.
-- Melissa
I'll get back on the bike soon, I promise!